JPH06159336A - Metallic expansion plug - Google Patents

Abstract

PURPOSE: To provide an expansible metal plug capable of being inserted surely and incapable of turning in a comparatively small bore hole and of being tightened quickly and sturdily by forming the outside contour of an expansion tab into a polygonal shape. CONSTITUTION: An expansible metal plug 1 has a square cross section, but may have another polygonal section, for example hexagonal. The forefront of the plug 1 is divided into four square expansion tabs 3 by slits 2 which is in parallel with the side faces. The inner surface 4 extends conically and is provided with threads. The length of the diameter or diagonal of the circumscribing circle to the outer cross section is greater than the diameter of a plug admitting hole 5. The angle region of the plug 1 is provided with a notch 6 directed sideways with respect to the axial direction. The plug 1 is inserted into the plug admitting hole 5. At this time, the safety for rotation is secured by the angle parts of the tabs 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a metal expansion plug,
The cylindrical segmented expansion tongue has a conical inner surface with threads.

[0002]

2. Description of the Prior Art Metal expansion plugs with a circular cross section require precisely matching plug receiving holes. Even so, the metal expansion plug easily rotates together when tightening the tightening screw. As a result, it is difficult to fix it, and the holding force is reduced.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a metal expansion plug which can be securely and non-rotatably inserted into a relatively small bore hole and can be fast and immovably fastened.

[0004]

According to the present invention, the above-mentioned problems can be solved by forming the outer contour of the extended tongue portion into a polygonal shape.

[0005]

The expansion plug of the invention differs from that of the prior art in that the axially extending corners of the expansion tongue ensure positive guidance in the plug receiving hole and prevent rotation of the metal expansion plug. That is the point of blocking. The corners of the expansion tongue are pushed into the wall of the plug receiving hole with a high specific pressure during the expansion operation, which ensures a secure retention. Metal expansion plugs are suitable for concrete work and solid and hollow wall work.

A quadrilateral expansion tongue can be achieved by forming four expanding tongues with a square cross-section inside the square outer cross-section by means of two slits parallel to the outer surface. Is. In this case, high surface pressure is achieved at the corners of the extended tongue.

The number of axial tightening corners is determined by forming four expanding tongues with a triangular cross-section inside a square outer cross-section by means of two diagonal slits. You can increase this.

A reliable guiding action when inserting the metal expansion plug into the plug receiving hole is achieved by the circumscribed circle defined by the polygonal outer contour having a diameter larger than the diameter of the expansion plug receiving hole. To be done.

The safety against dehiscence can be increased by arranging a notch extending transversely to the axial direction on the outer side of the expanding tongue.

[0010]

Embodiments of the present invention will now be described with reference to the drawings.

The illustrated metal expansion plug 1 has a square cross section. However, it is also possible to have another polygonal cross section, for example a hexagonal cross section. Metal plug 1 at the tip
Is divided into four square extension tongues 3 by slits 2 parallel to the sides. The inner surface 4 extends conically and has threads. The diameter of the circumscribing circle or the length of the diagonal line of the outer cross section is larger than the diameter of the expansion receiving hole 5.

In the corner area of the metal expansion plug 1, a notch 6 is formed which is oriented laterally with respect to the axial direction.

The metal expansion plug 1 is inserted into the expansion plug receiving hole 5 in a manner as shown in FIG. At this time, the corners of the extended tongue 3 ensure the safety against rotation. When rotating a tightening screw (not shown) with machined threads,
The metal expansion plug does not rotate in the plug receiving hole. During screwing, the expansion tongue 3 is expanded in a known manner as shown in the left half of FIG. The notch 6 contributes to increase the safety of dehiscence.

[Brief description of drawings]

FIG. 1 is a side view of a metal expansion plug according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a sectional view of a metal expansion plug.

[Explanation of symbols]

 1 Metal Expansion Plug 2 Slit 3 Expansion Tongue 4 Inner Surface 5 Plug Reception Hole 6 Notch

Claims (5)

[Claims] 1. The outer contour of the expansion tongue (3) in the form of a metal expansion plug whose cylindrical segment-shaped expansion tongue has a conical inner surface with threads. A metal expansion plug having a polygonal shape. 2. Inside the square outer cross section, four extension tongues (3) with a square cross section are formed by two slits parallel to the outer surface. The metal expansion plug according to claim 1. 3. Inside the square outer cross-section, two extended tongues with a triangular cross-section are formed by two diagonal slits. Item 1. A metal expansion plug according to item 1. 4. The circumscribing circle defined by the polygonal outer contour has a diameter larger than the diameter of the plug receiving hole (5). The metal expansion plug according to item 1. 5. A notch (6) extending transversely to the axial direction is arranged on the outer side of the expanding tongue (3), in accordance with one of the preceding claims. The described metal expansion plug.